Malicious RTF — malware analysis report

Static analysis result for SHA-256 8f02443e60bace0a…

MALICIOUS

RTF

1.02 MB
MD5: 4126a02a7c1813d85e7aebae88257220 SHA-1: c84b7d02f15e5edd969f5815433321d2beb3784f SHA-256: 8f02443e60bace0a38ca66a09f628b5a5cb06e7ecc69011ed27b879f4eaa11c9
280 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The RTF file contains multiple indicators of malicious OLE object embedding, specifically related to CVE-2017-8570, which is known to drop SCT scripts. The document body explicitly instructs the user to 'click Enable Editing', a common lure to bypass macro security. The presence of large hex data blocks within OLE objects further suggests a hidden payload. The combination of these factors strongly indicates an attempt to execute a secondary stage.

Heuristics 8

  • Composite Moniker — CVE-2017-8570 (drops SCT script) critical CVE related CVE_2017_8570
    RTF \objdata decodes to OLE data containing the Composite Moniker — CVE-2017-8570 (drops SCT script) CLSID — the vulnerable control/moniker is embedded directly in the document's object stream, the delivery shape of this exploit. RTF objects auto-render when Word opens the file.
  • Composite Moniker in RTF OLE object high CVE related RTF_COMPOSITE_MONIKER_RELATED
    RTF contains Composite Moniker CLSID in OLE object context, but no nearby scriptlet/SCT payload was confirmed. Treat as related moniker attack-surface evidence rather than proof of CVE-2017-8570 exploitation.
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \objupdate forces OLE activation high RTF_OBJUPDATE
    RTF contains \objupdate — forces automatic OLE object instantiation when the document is opened, bypassing user interaction. Almost exclusively seen in Equation Editor exploit documents.
  • Large hex data blocks in OLE object high RTF_EXCESSIVE_HEX
    RTF contains ~1037KB of hex-encoded data inside \objdata sections — may hide a payload
  • OLE object data medium RTF_OBJDATA
    RTF contains 4 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000966.bin
76cd9883ba8bdf94da9476519187b0fd8bd76c90611689969b559282f8888e83
rtf-objdata-decoded RTF \objdata at offset 0x966 408276 bytes
objdata_01_off00007115.bin
7a584ef30b63b7b980d3abdb62f7dc3f93b4b1c976e29fdade230dfc4ac17fde
rtf-objdata-decoded RTF \objdata at offset 0x7115 408249 bytes
objdata_02_off000d66bc.bin
51ef705eef602ac6eb91c2063c8f50d4e54b5e051b60429031d41133bc7df645
rtf-objdata-decoded RTF \objdata at offset 0xD66BC 2632 bytes
objdata_03_off000d7c5f.bin
e8d4fe950caed6dcfde26f4b616825bbe11b93458425974b7d075167f675abf7
rtf-objdata-decoded RTF \objdata at offset 0xD7C5F 12297 bytes